Grind the cacao nibs into a powder using a spice grinder. Combine with the chili powder, brown sugar, salt, smoked paprika, and a few grinds of black pepper. Use a fork to whisk the spices together.

Remove the steaks from the fridge and pat them dry with a paper towel. Sprinkle both sides generously with the spice mixture, and use your hands to rub the spices into the meat. Set aside at room temperature for 30 minutes or refrigerate for up to 8 hours. (If refrigerating, remove the steak from the oven 30 minutes before cooking so it warms to room temperature.)

To prepare the butter, whisk the bourbon and maple syrup together with a fork. Combine this with the butter in a small bowl and use the fork to begin mashing the liquid into the butter. As the butter softens further, move from mashing to whisking. At first, it may not seem like the liquid will mix with the butter, but keep going until most of the liquid has been absorbed. Scrape the butter onto a square of wax paper. Roll it up and twist the ends. Refrigerate until you're ready to serve the steaks.

To cook the steak, position a rack about 6 inches below the broiler element in your oven. Place a cast-iron or oven-safe skillet on the rack and turn on the broiler to high. Let the oven and the pan heat for about 5 minutes — until a of water splashed on the skillet evaporates immediately.

Turn on a kitchen fan or open a window. Remove the skillet from the oven using thick oven mitts and place over high heat on the stovetop. Add a splash of oil to the pan and swirl to coat the bottom.

Using kitchen tongs, place the steaks in the pan — they should begin sizzling immediately. Cook for 30 seconds, then use the tongs to flip them to the other side. Cook another 30 seconds, then place the pan in the oven under the broiler. Cook for 2 minutes in the oven, then (very carefully!) pull out the skillet and flip the steaks again. Place the skillet back under the broiler and cook for 2 more minutes — a total of 4 minutes oven cooking time. At this point, the steaks are medium-rare. Cook in additional 1-minute intervals for more well-cooked steaks.

Remove the steaks from the oven and transfer to a cutting board. Tent with foil and rest for 5 minutes.

To serve, slice the steaks against the grain into thick slices and arrange on a plate. Add a pat of the maple-bourbon butter over top. Eat immediately.